CMake: Fix failing standalone tests on Windows

Due to the install prefix being changed for standalone tests,
the correct $qt_prefix/bin folder was not added to the PATH
environment variable when running tests.

Make sure to always include the the original qt install prefix,
even if a different install prefix is specified when configuring
standalone tests.

Amends 39090ea15c41eded8a233ec2633c0c657280297c

Change-Id: I22aab732bb2bb679074a811d28d8209e1d535df3
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

2 files changed, 29 insertions, 4 deletions

diff --git a/cmake/QtBuild.cmake b/cmake/QtBuild.cmake
index 6375ffdca7..933fc367a6 100644
--- a/cmake/QtBuild.cmake
+++ b/cmake/QtBuild.cmake
@@ -3310,17 +3310,34 @@ function(qt_add_test name)
     if (arg_TIMEOUT)
         set_tests_properties(${name} PROPERTIES TIMEOUT ${arg_TIMEOUT})
     endif()
-    # Get path to qtbase/bin, then prepend this path containing the shared libraries to PATH
-    set(INSTALL_PREFIX_BIN "${CMAKE_INSTALL_PREFIX}/${INSTALL_BINDIR}")
-    set(test_env_path "PATH=${CMAKE_CURRENT_BINARY_DIR}${QT_PATH_SEPARATOR}${INSTALL_PREFIX_BIN}${QT_PATH_SEPARATOR}$ENV{PATH}")
+
+    # Get path to <original_qtbase_install_prefix>/bin, as well as CMAKE_INSTALL_PREFIX/bin, then
+    # prepend them to the PATH environment variable.
+    # It's needed on Windows to find the shared libraries and plugins.
+    # original_qtbase_install_prefix is the CMAKE_INSTALL_PREFIX specified when building qtbase.
+    # The regular CMAKE_INSTALL_PREFIX can be different for example when building standalone tests.
+    # Latest CMAKE_INSTALL_PREFIX takes priority for the PATH environment variable.
+    set(install_prefixes "${CMAKE_INSTALL_PREFIX}")
+    if(QT_BUILD_INTERNALS_ORIGINAL_INSTALL_PREFIX)
+        list(APPEND install_prefixes "${QT_BUILD_INTERNALS_ORIGINAL_INSTALL_PREFIX}")
+    endif()
+
+    set(test_env_path "PATH=${CMAKE_CURRENT_BINARY_DIR}")
+    foreach(install_prefix ${install_prefixes})
+        set(test_env_path "${test_env_path}${QT_PATH_SEPARATOR}${install_prefix}/${INSTALL_BINDIR}")
+    endforeach()
+    set(test_env_path "${test_env_path}${QT_PATH_SEPARATOR}$ENV{PATH}")
     string(REPLACE ";" "\;" test_env_path "${test_env_path}")
     set_property(TEST "${name}" APPEND PROPERTY ENVIRONMENT "${test_env_path}")
     set_property(TEST "${name}" APPEND PROPERTY ENVIRONMENT "QT_TEST_RUNNING_IN_CTEST=1")
 
     # Add the install prefix to list of plugin paths when doing a prefix build
     if(NOT QT_INSTALL_DIR)
-        list(APPEND plugin_paths "${CMAKE_INSTALL_PREFIX}/${INSTALL_PLUGINSDIR}")
+        foreach(install_prefix ${install_prefixes})
+            list(APPEND plugin_paths "${install_prefix}/${INSTALL_PLUGINSDIR}")
+        endforeach()
     endif()
+
     #TODO: Collect all paths from known repositories when performing a super
     # build.
     list(APPEND plugin_paths "${PROJECT_BINARY_DIR}/${INSTALL_PLUGINSDIR}")
diff --git a/cmake/QtBuildInternalsExtra.cmake.in b/cmake/QtBuildInternalsExtra.cmake.in
index 5278890337..ea945a913d 100644
--- a/cmake/QtBuildInternalsExtra.cmake.in
+++ b/cmake/QtBuildInternalsExtra.cmake.in
@@ -10,6 +10,14 @@ set(QT_BUILD_INTERNALS_PATH "${CMAKE_CURRENT_LIST_DIR}")
 set(CMAKE_INSTALL_PREFIX @CMAKE_INSTALL_PREFIX@ CACHE PATH
     "Install path prefix, prepended onto install directories." FORCE)
 
+# Save the original install prefix in an additional variable.
+# While CMAKE_INSTALL_PREFIX may be overridden in certain cases (like for standalone tests building
+# or for singular qt-cmake-standalone-test usage), we still need the original qtbase install prefix
+# to know where the shared libraries are located to inject them into PATH when running tests via
+# ctest.
+set(QT_BUILD_INTERNALS_ORIGINAL_INSTALL_PREFIX @CMAKE_INSTALL_PREFIX@ CACHE PATH
+    "Original install prefix specified when building qtbase." FORCE)
+
 # Propagate developer builds to other modules via BuildInternals package.
 if(@FEATURE_developer_build@)
     set(FEATURE_developer_build ON CACHE BOOL "Developer build." FORCE)